X-Git-Url: https://git.cameronkatri.com/pw-darwin.git/blobdiff_plain/9ac072c5534fe9a159cc808b8c4ea641353c3306..d3c118ef948d741a56d11a7cbe23094958dffe72:/libutil/pw_util.c?ds=sidebyside

diff --git a/libutil/pw_util.c b/libutil/pw_util.c
index 75459e3..112b6d8 100644
--- a/libutil/pw_util.c
+++ b/libutil/pw_util.c
@@ -1,4 +1,6 @@
-/*-
+/*--
+ * SPDX-License-Identifier: BSD-3-Clause
+ *
  * Copyright (c) 1990, 1993, 1994
  *	The Regents of the University of California.  All rights reserved.
  * Copyright (c) 2002 Networks Associates Technology, Inc.
@@ -17,7 +19,7 @@
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
- * 4. Neither the name of the University nor the names of its contributors
+ * 3. Neither the name of the University nor the names of its contributors
  *    may be used to endorse or promote products derived from this software
  *    without specific prior written permission.
  *
@@ -34,13 +36,9 @@
  * SUCH DAMAGE.
  */
 
-#ifndef lint
-#if 0
-static const char sccsid[] = "@(#)pw_util.c	8.3 (Berkeley) 4/2/94";
-#endif
-static const char rcsid[] =
-  "$FreeBSD$";
-#endif /* not lint */
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+__SCCSID("@(#)pw_util.c	8.3 (Berkeley) 4/2/94");
 
 /*
  * This file is used by all the "password" programs; vipw(8), chpass(1),
@@ -58,7 +56,6 @@ static const char rcsid[] =
 #include <err.h>
 #include <fcntl.h>
 #include <inttypes.h>
-#include <libgen.h>
 #include <paths.h>
 #include <pwd.h>
 #include <signal.h>
@@ -67,7 +64,7 @@ static const char rcsid[] =
 #include <string.h>
 #include <unistd.h>
 
-#include <libutil.h>
+#include "libutil.h"
 
 static pid_t editpid = -1;
 static int lockfd = -1;
@@ -179,11 +176,8 @@ pw_lock(void)
 	for (;;) {
 		struct stat st;
 
-		lockfd = open(masterpasswd, O_RDONLY, 0);
-		if (lockfd < 0 || fcntl(lockfd, F_SETFD, 1) == -1)
-			err(1, "%s", masterpasswd);
-		/* XXX vulnerable to race conditions */
-		if (flock(lockfd, LOCK_EX|LOCK_NB) == -1) {
+		lockfd = flopen(masterpasswd, O_RDONLY|O_NONBLOCK|O_CLOEXEC, 0);
+		if (lockfd == -1) {
 			if (errno == EWOULDBLOCK) {
 				errx(1, "the password db file is busy");
 			} else {
@@ -229,7 +223,7 @@ pw_tmp(int mfd)
 		errno = ENAMETOOLONG;
 		return (-1);
 	}
-	if ((tfd = mkstemp(tempname)) == -1)
+	if ((tfd = mkostemp(tempname, 0)) == -1)
 		return (-1);
 	if (mfd != -1) {
 		while ((nr = read(mfd, buf, sizeof(buf))) > 0)
@@ -318,7 +312,7 @@ pw_edit(int notsetuid)
 			(void)setuid(getuid());
 		}
 		errno = 0;
-		execlp(editor, basename(editor), tempname, (char *)NULL);
+		execlp(editor, editor, tempname, (char *)NULL);
 		_exit(errno);
 	default:
 		/* parent */
@@ -347,7 +341,8 @@ pw_edit(int notsetuid)
 	sigprocmask(SIG_SETMASK, &oldsigset, NULL);
 	if (stat(tempname, &st2) == -1)
 		return (-1);
-	return (st1.st_mtime != st2.st_mtime);
+	return (st1.st_mtim.tv_sec != st2.st_mtim.tv_sec ||
+	    st1.st_mtim.tv_nsec != st2.st_mtim.tv_nsec);
 }
 
 /*
@@ -406,23 +401,56 @@ pw_make(const struct passwd *pw)
 	    pw->pw_passwd, (uintmax_t)pw->pw_uid, (uintmax_t)pw->pw_gid,
 	    pw->pw_class, (uintmax_t)pw->pw_change, (uintmax_t)pw->pw_expire,
 	    pw->pw_gecos, pw->pw_dir, pw->pw_shell);
-	return line;
+	return (line);
+}
+
+/*
+ * Make a passwd line (in v7 format) out of a struct passwd
+ */
+char *
+pw_make_v7(const struct passwd *pw)
+{
+	char *line;
+
+	asprintf(&line, "%s:*:%ju:%ju:%s:%s:%s", pw->pw_name,
+	    (uintmax_t)pw->pw_uid, (uintmax_t)pw->pw_gid,
+	    pw->pw_gecos, pw->pw_dir, pw->pw_shell);
+	return (line);
 }
 
 /*
- * Copy password file from one descriptor to another, replacing or adding
- * a single record on the way.
+ * Copy password file from one descriptor to another, replacing, deleting
+ * or adding a single record on the way.
  */
 int
 pw_copy(int ffd, int tfd, const struct passwd *pw, struct passwd *old_pw)
 {
-	char buf[8192], *end, *line, *p, *q, *r, t;
+	char *buf, *end, *line, *p, *q, *r, *tmp;
 	struct passwd *fpw;
-	size_t len;
+	const struct passwd *spw;
+	size_t len, size;
 	int eof, readlen;
+	char t;
 
-	if ((line = pw_make(pw)) == NULL)
-		return (-1);
+	if (old_pw == NULL && pw == NULL)
+			return (-1);
+
+	spw = old_pw;
+	/* deleting a user */
+	if (pw == NULL) {
+		line = NULL;
+	} else {
+		if ((line = pw_make(pw)) == NULL)
+			return (-1);
+	}
+
+	/* adding a user */
+	if (spw == NULL)
+		spw = pw;
+
+	/* initialize the buffer */
+	if ((buf = malloc(size = 1024)) == NULL)
+		goto err;
 
 	eof = 0;
 	len = 0;
@@ -437,10 +465,16 @@ pw_copy(int ffd, int tfd, const struct passwd *pw, struct passwd *old_pw)
 		if (q >= end) {
 			if (eof)
 				break;
-			if ((size_t)(q - p) >= sizeof(buf)) {
-				warnx("passwd line too long");
-				errno = EINVAL; /* hack */
-				goto err;
+			while ((size_t)(q - p) >= size) {
+				if ((tmp = reallocarray(buf, 2, size)) == NULL) {
+					warnx("passwd line too long");
+					goto err;
+				}
+				p = tmp + (p - buf);
+				q = tmp + (q - buf);
+				end = tmp + (end - buf);
+				buf = tmp;
+				size = size * 2;
 			}
 			if (p < end) {
 				q = memmove(buf, p, end - p);
@@ -448,7 +482,7 @@ pw_copy(int ffd, int tfd, const struct passwd *pw, struct passwd *old_pw)
 			} else {
 				p = q = end = buf;
 			}
-			readlen = read(ffd, end, sizeof(buf) - (end - buf));
+			readlen = read(ffd, end, size - (end - buf));
 			if (readlen == -1)
 				goto err;
 			else
@@ -457,7 +491,7 @@ pw_copy(int ffd, int tfd, const struct passwd *pw, struct passwd *old_pw)
 				break;
 			end += len;
 			len = end - buf;
-			if (len < (ssize_t)sizeof(buf)) {
+			if (len < size) {
 				eof = 1;
 				if (len > 0 && buf[len - 1] != '\n')
 					++len, *end++ = '\n';
@@ -489,7 +523,7 @@ pw_copy(int ffd, int tfd, const struct passwd *pw, struct passwd *old_pw)
 		 */
 
 		*q = t;
-		if (fpw == NULL || strcmp(fpw->pw_name, pw->pw_name) != 0) {
+		if (fpw == NULL || strcmp(fpw->pw_name, spw->pw_name) != 0) {
 			/* nope */
 			if (fpw != NULL)
 				free(fpw);
@@ -506,17 +540,21 @@ pw_copy(int ffd, int tfd, const struct passwd *pw, struct passwd *old_pw)
 		}
 		free(fpw);
 
-		/* it is, replace it */
-		len = strlen(line);
-		if (write(tfd, line, len) != (int)len)
-			goto err;
-
+		/* it is, replace or remove it */
+		if (line != NULL) {
+			len = strlen(line);
+			if (write(tfd, line, len) != (int)len)
+				goto err;
+		} else {
+			/* when removed, avoid the \n */
+			q++;
+		}
 		/* we're done, just copy the rest over */
 		for (;;) {
 			if (write(tfd, q, end - q) != end - q)
 				goto err;
 			q = buf;
-			readlen = read(ffd, buf, sizeof(buf));
+			readlen = read(ffd, buf, size);
 			if (readlen == 0)
 				break;
 			else
@@ -528,16 +566,22 @@ pw_copy(int ffd, int tfd, const struct passwd *pw, struct passwd *old_pw)
 		goto done;
 	}
 
-	/* if we got here, we have a new entry */
+	/* if we got here, we didn't find the old entry */
+	if (line == NULL) {
+		errno = ENOENT;
+		goto err;
+	}
 	len = strlen(line);
 	if ((size_t)write(tfd, line, len) != len ||
 	    write(tfd, "\n", 1) != 1)
 		goto err;
  done:
 	free(line);
+	free(buf);
 	return (0);
  err:
 	free(line);
+	free(buf);
 	return (-1);
 }
 
@@ -557,43 +601,50 @@ pw_tempname(void)
 struct passwd *
 pw_dup(const struct passwd *pw)
 {
+	char *dst;
 	struct passwd *npw;
 	ssize_t len;
 
-	len = sizeof(*npw) +
-	    (pw->pw_name ? strlen(pw->pw_name) + 1 : 0) +
-	    (pw->pw_passwd ? strlen(pw->pw_passwd) + 1 : 0) +
-	    (pw->pw_class ? strlen(pw->pw_class) + 1 : 0) +
-	    (pw->pw_gecos ? strlen(pw->pw_gecos) + 1 : 0) +
-	    (pw->pw_dir ? strlen(pw->pw_dir) + 1 : 0) +
-	    (pw->pw_shell ? strlen(pw->pw_shell) + 1 : 0);
+	len = sizeof(*npw);
+	if (pw->pw_name != NULL)
+		len += strlen(pw->pw_name) + 1;
+	if (pw->pw_passwd != NULL)
+		len += strlen(pw->pw_passwd) + 1;
+	if (pw->pw_class != NULL)
+		len += strlen(pw->pw_class) + 1;
+	if (pw->pw_gecos != NULL)
+		len += strlen(pw->pw_gecos) + 1;
+	if (pw->pw_dir != NULL)
+		len += strlen(pw->pw_dir) + 1;
+	if (pw->pw_shell != NULL)
+		len += strlen(pw->pw_shell) + 1;
 	if ((npw = malloc((size_t)len)) == NULL)
 		return (NULL);
 	memcpy(npw, pw, sizeof(*npw));
-	len = sizeof(*npw);
-	if (pw->pw_name) {
-		npw->pw_name = ((char *)npw) + len;
-		len += sprintf(npw->pw_name, "%s", pw->pw_name) + 1;
+	dst = (char *)npw + sizeof(*npw);
+	if (pw->pw_name != NULL) {
+		npw->pw_name = dst;
+		dst = stpcpy(npw->pw_name, pw->pw_name) + 1;
 	}
-	if (pw->pw_passwd) {
-		npw->pw_passwd = ((char *)npw) + len;
-		len += sprintf(npw->pw_passwd, "%s", pw->pw_passwd) + 1;
+	if (pw->pw_passwd != NULL) {
+		npw->pw_passwd = dst;
+		dst = stpcpy(npw->pw_passwd, pw->pw_passwd) + 1;
 	}
-	if (pw->pw_class) {
-		npw->pw_class = ((char *)npw) + len;
-		len += sprintf(npw->pw_class, "%s", pw->pw_class) + 1;
+	if (pw->pw_class != NULL) {
+		npw->pw_class = dst;
+		dst = stpcpy(npw->pw_class, pw->pw_class) + 1;
 	}
-	if (pw->pw_gecos) {
-		npw->pw_gecos = ((char *)npw) + len;
-		len += sprintf(npw->pw_gecos, "%s", pw->pw_gecos) + 1;
+	if (pw->pw_gecos != NULL) {
+		npw->pw_gecos = dst;
+		dst = stpcpy(npw->pw_gecos, pw->pw_gecos) + 1;
 	}
-	if (pw->pw_dir) {
-		npw->pw_dir = ((char *)npw) + len;
-		len += sprintf(npw->pw_dir, "%s", pw->pw_dir) + 1;
+	if (pw->pw_dir != NULL) {
+		npw->pw_dir = dst;
+		dst = stpcpy(npw->pw_dir, pw->pw_dir) + 1;
 	}
-	if (pw->pw_shell) {
-		npw->pw_shell = ((char *)npw) + len;
-		len += sprintf(npw->pw_shell, "%s", pw->pw_shell) + 1;
+	if (pw->pw_shell != NULL) {
+		npw->pw_shell = dst;
+		dst = stpcpy(npw->pw_shell, pw->pw_shell) + 1;
 	}
 	return (npw);
 }